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101.
Repeated-sprint training often involves short sprints separated by inadequate recovery intervals. The effects of interval duration on metabolic and performance parameters are unclear. We compared the effects of two training programmes, differing in rest interval duration, on muscle (vastus lateralis) metabolism and sprint performance. Sixteen men trained three times a week for 8 weeks, each training session comprising 2-3 sets of two 80-m sprints. Sprints were separated by 10 s (n = 8) or 1 min (n = 8). Both training programmes improved performance in the 100-, 200-, and 300-m sprints, but the improvement was greater in the 10-s group during the final 100 m of the 200- and 300-m runs. Independent of interval duration, training mitigated the drop of muscle ATP after two 80-m sprints. The drop in phosphocreatine and the increases in glucose-6-phosphate and fructose-6-phosphate after two 80-m sprints were greater in the 10-s group. In conclusion, training with a limited number of repeated short sprints (≤10 s) may be more effective in improving speed maintenance in 200- and 300-m runs when performed with a 1:1 rather than a 1:6 exercise-to-rest ratio. This may be due to a greater activation of glycolysis caused, in part, by the limited resynthesis of phosphocreatine during the very short rest interval.  相似文献   
102.
The aim of this study was to examine the effectiveness of either a standard care programme (n = 9) or a 12-week supported exercise programme (n = 10) on glycaemic control, β-cell responsiveness, insulin resistance, and lipid profiles in newly diagnosed Type 2 diabetes patients. The standard care programme consisted of advice to exercise at moderate to high intensity for 30 min five times a week; the supported exercise programme consisted of three 60-min supported plus two unsupported exercise sessions per week. Between-group analyses demonstrated a difference for changes in low-density lipoprotein cholesterol only (standard care programme 0.01 mmol · L(-1), supported exercise programme -0.6 mmol · L(-1); P = 0.04). Following the standard care programme, within-group analyses demonstrated a significant reduction in waist circumference, whereas following the supported exercise programme there were reductions in glycosylated haemoglobin (6.4 vs. 6.0%; P = 0.007), waist circumference (101.4 vs. 97.2 cm; P = 0.021), body mass (91.7 vs. 87.9 kg; P = 0.007), body mass index (30.0 vs. 28.7 kg · m(-2); P = 0.006), total cholesterol (5.3 vs. 4.6 mmol · L(-1); P = 0.046), low-density lipoprotein cholesterol (3.2 vs. 2.6 mmol · L(-1); P = 0.028), fasting β-cell responsiveness (11.5 × 10(-9) vs. 7.0 × 10(-9) pmol · kg(-1) · min(-1); P = 0.009), and insulin resistance (3.0 vs. 2.1; P = 0.049). The supported exercise programme improved glycaemic control through enhanced β-cell function associated with decreased insulin resistance and improved lipid profile. This research highlights the need for research into unsupported and supported exercise programmes to establish more comprehensive lifestyle advice for Type 2 diabetes patients.  相似文献   
103.
The agreement between self-reported and objective estimates of activity energy expenditure was evaluated in adolescents by age, sex, and weight status. Altogether, 403 participants (217 females, 186 males) aged 13-16 years completed a 3-day physical activity diary and wore a GT1M accelerometer on the same days. Partial correlations (controlling for body mass) were used to determine associations between estimated activity energy expenditure (kcal · min(-1)) from the diary and accelerometry. Differences in the magnitude of the correlations were examined using Fisher's r to z transformations. Bland-Altman procedures were used to determine concordance between the self-reported and objective estimates. Partial correlations between assessments of activity energy expenditure (kcal · min(-1)) did not differ significantly by age (13-14 years: r = 0.41; 15-16 years: r = 0.42) or weight status (normal weight: r = 0.42; overweight: r = 0.39). The magnitude of the association was significantly affected by sex (Δr = 0.11; P < 0.05). The agreement was significantly higher in males than in females. The relationship between activity energy expenditure assessed by the objective method and the 3-day diary was moderate (controlling for weight, correlations ranged between 0.33 and 0.44). However, the 3-day diary revealed less agreement in specific group analyses; it markedly underestimated activity energy expenditure in overweight/obese and older adolescents. The assessment of activity energy expenditure is complex and may require a combination of methods.  相似文献   
104.
We assessed how golfers cope with the commonly observed systematic overshoot errors in the perception of the direction between the ball and the hole. Experiments 1 and 2, in which participants were required to rotate a pointer such that it pointed to the center of the hole, showed that errors in perceived direction (in degrees of deviation from the perfect aiming line) are destroyed when the head is constrained to move within a plane perpendicular to the green. Experiment 3 compared the errors in perceived direction and putting errors of novice and skilled players. Unlike the perceived direction, putting accuracy (in degrees of deviation from the perfect aiming line) was not affected by head position. Novices did show a rightward putting error, while skilled players did not. We argue that the skill-related differences in putting accuracy reflect a process of recalibration. Implications for aiming in golf are discussed.  相似文献   
105.
Using objectification theory (Fredrickson & Roberts, 1997), this study tested the interaction between self-objectification, appearance evaluation, and self-esteem in predicting body satisfaction and mood states. Participants (N = 93) were physically active female university students. State self-objectification was manipulated by participants wearing tight revealing exercise attire (experimental condition) or baggy exercise clothes (control condition). Significant interactions emerged predicting depression, anger, fatness, and satisfaction with body shape and size. For participants in the self-objectification condition who had low (as opposed to high) appearance evaluation, low self-esteem was associated with high depression, anger, and fatness and low satisfaction with body shape and size. In contrast, for participants with high self-esteem, these mood and body satisfaction states were more favorable irrespective of their levels of appearance evaluation. For female exercisers, self-esteem-enhancing strategies may protect against some of the negative outcomes of self-objectification.  相似文献   
106.
2014年6月3日下午,罗伯特·G·皮卡德教授在清华大学杭敏教授等人的陪同下,来到了中国人民大学新闻学院,同喻国明教授及广告与传媒经济系的教师及博士生展开了将近两个小时的座谈。对话内容围绕2014年"世界传媒经济暨管理学术会议"的研究热点、皮卡德教授所在的路透研究所的最新研究课题展开,并对未来传媒经济发展趋势进行了展望:包括基于互联网的传媒经济形态的变化、媒介整合盈利模式、大数据在新闻业的应用、新闻的自动化和个性化生产等。  相似文献   
107.
本文分析了美国联邦财政对教育的资助及制定资助政策的相关问题:联邦或州政府的职责;教育成本的基本构成;在指导性财政资助中联邦政府和纳税人的作用;学生获得资助或补贴的渠道及相应的国家政策;国家对公立学院和大学的资助范围等。这对于我国筹措教育资金,分解教育成本具有某些启示。  相似文献   
108.
OBJECTIVE: The United States General Accounting Office (United States General Accounting Office [USGAO], 1989) report on out-of-home care affirmed that the foster care system is in crisis. To shed light on some factors that influence retention, the study reported here asked "What factors influence the satisfaction of foster parents?" and "What factors influence the intent of licensed foster parents to continue to foster?" METHOD: A sample of 539 foster parents in eight urban counties in a large Midwestern state completed questionnaires aimed at addressing these questions. RESULTS: Some of the factors exerting the strongest influence on satisfaction were: feeling competent to handle the children who were placed; wanting to take in children who needed loving parents; no regrets about investment in foster children; foster mother's age; and agency social worker providing information and showing approval for a job well done. An example of factors exerting influence on intent to continue to foster include overall satisfaction, readiness to phone the social worker, number of foster boys in the home, being treated like one needed help oneself, and agency affiliation (private). CONCLUSIONS: Efforts to increase the supply of foster homes through recruitment is not enough. The support, training, and professional regard given to parents after they have begun the fostering task is of greater need. Based on analysis of the findings, implications for practice, programming, and policy are offered.  相似文献   
109.
Surgical management of gastric stump cancer: a report of 37 cases   总被引:3,自引:0,他引:3  
Objective: To observe the clinicopathological characteristics of gastric stump cancer (GSC) and evaluate the benefits of radical surgery of GSC. Methods: The clinicopathological characteristics and postoperative survival time of 37 GSC patients who underwent surgery were investigated retrospectively. The survival time was compared according to the type of surgical pTMN stage. Survival curves were traced by using Kaplan-Meier methods. Results: Most GSC (32/37) was detected in patients who had received Billroth Ⅱ reconstruction after partial gastrectomy for benign gastric disease. The lesser curvature side and the suture line of anastomosis were the most frequent sites where GSC occurred (27/37). Differentiated adenocarcinoma was the dominant histopathological type (24/37). The postoperative 5-year survival rate of early stage GSC patients (n=9) was significantly higher than advanced stage GSC (n=12) (55.6% vs 16.5%, xL2=1 1.48, P<0.01). Five-year survival rate of 21 GSC patients with radical resection were 75% (3/4) for stage Ⅰ, 60% (3/5) for stage Ⅱ, 14.2% (1/7) for stage Ⅲ, and 0% (0/5) for stage Ⅳ respectively.The median survival time of 21 GSC patients who underwent radical resection was longer than those undergoing palliative operation (43.0m vs 13.0m, xL2=36.31, P<0.01), the median survival time of stage Ⅳ patients with radical resection was 23.8months. Conclusions: Without remote metastasis, radical resection for GSC is possible, and is an effective way to improve the prognosis of GSC. Even in stage Ⅳ GSC, radical resection can still prolong the survival time. It is necessary for the patients with benign gastric diseases who received partial gastrectomy to carry out the endoscopy follow-up, especially in patients with Billroth Ⅱ reconstruction procedure at 15-20 years.  相似文献   
110.
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